[Zurück]

S. Majumdar, E.V. Sampathkumaran, St Berger, M. Della Mea, H. Michor, E. Bauer, M. Brando, J. Hemberger, A. Loidl:
"An unusual interplay among disorder, Kondo-effect and spin-glass behavior in the Kondo lattices: Ce₂Au_1-xCo_xSi₃ ";
Solid State Communications, 121 (2002), S. 665 - 668.

An unusual interplay among disorder, Kondo-effect and spin-glass behavior in the Kondo lattices, Ce2Au1-xCoxSi3

S. Majumdara, E. V. Sampathkumaran [Corresponding Author Contact Information] , [E-mail The Corresponding Author] , a, 1, St. Bergerb, M. Della Meab, H. Michorb, E. Bauerb, M. Brandoc, J. Hembergerc and A. Loidlc

a Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
b Institut f.Experimentalphysik, Vienna University of Technology, A-1040 Wien, Austria
c Experimentalphysik V, Elektronische Korrelationen und Magnetismus, Institut für Physik, Universität Augsburg, D-86135 Augsburg, Germany

Received 18 December 2001; revised 18 December 2001; accepted 22 January 2002 by C.N.R. Rao Available online 6 February 2002.

Abstract

We report the results of magnetic measurements for the solid solution Ce2Au1-xCoxSi3 . The results reveal that this solid solution is characterized by a magnetic phase diagram (plot of magnetic transition temperature versus x) unusual for Kondo lattices. In particular, the spin-glass freezing induced by disorder is observed only for the compositions at the weak coupling limit; as one approaches the quantum critical point by a gradual replacement of Au by Co, this disorder effect is surprisingly suppressed in favor of long range antiferromagnetic ordering in contrast to expectations. This unusual interplay between disorder, spin-glass freezing and the Kondo-effect calls for further refinement of theories on competition between magnetism and the Kondo effect.

http://dx.doi.org/10.1016/S0038-1098(02)00053-4